Question re: Compendium lens hood

[PViapiano]

Has anyone tried using a Mamiya lens bellows on a LF lens?

Was wondering if it would work?

[Greg Lockrey]

I use oversized rubber type shades all the time, you just have to pay attention to vigneting.

[Robert A. Zeichner]

I can't say I have had first hand experience with the Mamiya compendium, but all of the MF bellows-type shades made for specific lens/camera/format combinations have several problems in common: They have no provision for assymetrical adjustment and so they cannot follow the placement of the optical axis of the lens relative to the postion of the film. They are typically designed for the 6x6 or 6x7 format and so will either vignette on more panoramic formats like 5x7 or 4x10 or (and this is most likely) will allow large amounts of non-image forming light into the lens, reducing its effectiveness. They also do not take into consideration the typically larger coverage of LF lenses.

Round rubber shades at best, will eliminate sun flares and maybe protect the front rim of the lens from damage if bumped. Hats and dark slides are not much better. If you really want to see improvement in dynamic range and apparent sharpness, you need to eliminate all non-image forming light from entering the camera.

That said, if you read my lens shade article in the March/April edition of Photo-Techniques, you will see a suggestion for an inexpensive and extremely effective homemade shade that takes all of these issues into account and will make a noticeable difference in your negatives.

[ditkoofseppala]

For us unlucky ones who haven't seen the mag and can't get it, could you possibly describe your solution in usable detail on this thread? :)

I'm looking for an inexpensive, effective non-image-forming light exclusion solution, hopefully something that will include provision for mounting square gel or glass flat filters on a variety of lenses.

[Robert A. Zeichner]

What I've done essentially is to take a small 4-leaf barndoor assembly from an LTM Pepper 100 focusing Fresnel light fixture and clip it to a Tiffen 67M9 series 9 to 67mm adapter ring. Tiffen makes 72mm and 77mm versions as well for those with larger lenses. So now what I have is a four leaf lens shade that can be oriented to match the film direction (vertical or horizontal and for those with revolving backs, anything in between). I screw whatever filter I intend to use into the lens and then screw the shade into the filter. By observing through the clipped corners of my ground glass, I can see exactly when the leaves of the shade start to vignette. The shade adjustment is the last thing I do after composing, adjusting movements, setting aperture and so forth. The only other thing I've done is to put a black velvet elastic
Scrunchie (girl's hairband) around the place where the barndoor meets the adapter so as to trap any light that might leak in through the hinges. You will be amazed at how small a rectangular portal is required to effectively shade some of the longer lenses. In some instances, more than half the light entering the lens never reaches the film. That's a lot of non-image forming light completely avoided. You will instantly see a difference in the shadow detail of your negatives, particularly if you are using single coated or uncoated lenses or ones with huge coverage.

[ditkoofseppala]

Cool idea! It sounds simple, easy to put together, and effective. That's the kind of thing I love to hear, a cost-effective solution that's going to MAKE A DIFFERENCE to negative quality! Thank you very much.

[Rider]

Robert, is this the barndoor you used?

http://www.bhphotovideo.com/c/product/125380-REG/LTM_PAA225_4_Leaf_Barndoor_for_Pepper.html

[Robert A. Zeichner]

Yep, that's the one. Just clip it to a Tiffen 67M9 or a 72M9 or if you can find an S9 to S8 step down adapter, that will work the same as the 67M9. I used a couple of mini binder clips, Just slip a black velvet Scrunchie over it and away you go. You can use 67 to 52 step down rings or whatever size you require.

[Rider]

The barndoors are $47 and the 72M9 (couldn't find the 67M9) is $83 (see link below).

At $130 for just those two pieces, it's getting kind of pricey, unless you happen to have these things lying around.

http://www.bhphotovideo.com/bnh/controller/home?shs=72m9&ci=0&sb=ps&pn=1&sq=desc&InitialSearch=yes&O=product.jsp&A=search&Q=*&bhs=t

[Robert A. Zeichner]

The barndoors are $47 and the 72M9 (couldn't find the 67M9) is $83 (see link below).

At $130 for just those two pieces, it's getting kind of pricey, unless you happen to have these things lying around.

http://www.bhphotovideo.com/bnh/controller/home?shs=72m9&ci=0&sb=ps&pn=1&sq=desc&InitialSearch=yes&O=product.jsp&A=search&Q=*&bhs=t

I hear what you are saying. It's expensive if you think of it as a lens shade in the classical sense, a round, rubber thing that might prevent a sun flare from ruining a picture. If you see what this does (and you need to compare negatives made with and without it), you will begin to think of it as a lens performance enhancer that will make your uncoated lenses behave more like coated ones and your single coated lenses more like multi-coated ones. At $130, plus whatever adapters you need to facilitate screwing into the various lenses you own, it is a cheap upgrade to every lens you own. Plus, you will never have bellows flare.

That said, you might try and find a Tiffen 89 step-up ring. This is the functional equivalent of the 67M9. I did just happen to have all of this stuff in my vast collection of rings and things. I see this stuff all the time at used camera shows.

[Helen Bach]

You might like to consider some of the other barn doors that are available for small lights - some of which are more versatile than the Pepper ones:

Dedo (http://www.bhphotovideo.com/c/product/382390-REG/Dedolight_DBD8_8_Leaf_Barndoor_Set.html)

Lowel i-Light (http://www.bhphotovideo.com/c/product/31758-REG/Lowel_IP20_4_Leaf_Barndoor_Set.html)

Lee adapter rings (http://www.bhphotovideo.com/c/product/87119-REG/LEE_Filters_AR067_Adapter_Ring_67mm.html) could be an alternative to the Tiffen ones.

Personally I prefer compendium shades with mattes (masks).

Best,
Helen

[Robert A. Zeichner]

Quite right. There are the ones Helen mentions as well as ones from Arri, DeSisti, Anton Bauer and Cool-Lux. Sachtler and Kobold most likely have small barn doors as well. I used the LTM Pepper doors because that is what I already owned and they just happened to couple with the S9 adapter rings perfectly, hence the need for nothing more than two mini-binder clips from the office supply to clip them together.

Dedo (http://www.bhphotovideo.com/c/product/382390-REG/Dedolight_DBD8_8_Leaf_Barndoor_Set.html)

Lowel i-Light (http://www.bhphotovideo.com/c/product/31758-REG/Lowel_IP20_4_Leaf_Barndoor_Set.html)

Lee adapter rings (http://www.bhphotovideo.com/c/product/87119-REG/LEE_Filters_AR067_Adapter_Ring_67mm.html) could be an alternative to the Tiffen ones.

For that matter, B&W (Century-Schneider) offer rings as well, although I have not actually played with one of thier series rings.

Personally I prefer compendium shades with mattes (masks).
[/QUOTE]

This certainly is the standard in the motion picture industry, but in the world of view camera photography, the ability to reposition the placement of the rectangular cutout relative to the optical axis is critical if you want to exclude all the non-image forming light that might pass through the lens when employing movements. Another factor is aperture. The size of the mask needs to change to accommdate larger or smaller apertures. The hard mattes used in the cine industry are sized for maximum aperture and in fact, several of them are sized to be used on a couple of different focal lengths of lenses which means that at best, they are optimized for the widest lens in the designated range and at the maximum aperture and at only one aspect ratio!

I would suggest just trying my idea with whatever you can scrounge up. Once you've made some comparison exposures and see the difference this type of system makes, you will be in a better position to access the $ value of what you need to get to do it more elegantly.

Bob

[Rider]

What exactly are "compendium shades with mattes (masks)"?

[Helen Bach]

This certainly is the standard in the motion picture industry, but in the world of view camera photography, the ability to reposition the placement of the rectangular cutout relative to the optical axis is critical if you want to exclude all the non-image forming light that might pass through the lens when employing movements. Another factor is aperture. The size of the mask needs to change to accommdate larger or smaller apertures. The hard mattes used in the cine industry are sized for maximum aperture and in fact, several of them are sized to be used on a couple of different focal lengths of lenses which means that at best, they are optimized for the widest lens in the designated range and at the maximum aperture and at only one aspect ratio!
...

Bob,

I don't think that there are quite as many practical disadvantages to the mask/compendium combination as you imagine. The point about using a matte with a matte box (or compendium shade) is that the distance from the front element (and hence the entrance pupil) to the matte can be changed, so you don't need a different matte for different apertures, different focal distances or, to a limited extent, different focal lengths. Even if you are unable to adjust the distance between the front element and the matte, the matte should be sized so that it encroaches a little on the periphery of the bundle of ray pencils at maximum aperture, so there may be very little difference between the optimum size of the matte at full aperture and at smaller apertures. Having written all that, even I don't think that such finessing is all that important.

The Lee compendium shade will allow you to move the matte in one direction to accomodate some lens movement. As the shade is square and can be rotated, you can choose to move it vertically or horizontally.

Now that Sinar stuff is selling for pennies on the dollar, the Sinar adjustable mask (Mask 2?) could be incorporated into non-Sinar shade systems. So far I have only used mine with a Sinar, however. It's a very handy thing.

No matter what one's personal preference for a method of effective shading is, the main point is that it is often surprisingly beneficial. Those of us who work in motion pictures use matte boxes, mattes/masks, eyebrows and flags as a matter of routine.

I understand a compendium shade to be a bellows lens hood, usually with one or more slots for filters at the back and a slot for a matte at the front. At least one of the filter slots may be rotatable. It can be mounted on the filter thread of the lens, or it can be mounted independently - independent mounting being preferable in most cases. The matte or mask is a simple piece of black card, plastic or metal with a cut-out that matches the aspect ratio of the format in use, and sized to cut out all the non-image forming light. Masks are very easy to make.

Best,
Helen